High-Dose Radiation Therapy is Critical in Treatment of Some Prostate Cancers

High-Dose Radiation Therapy is Critical in Treatment of Some Prostate Cancers

Dose escalation is critical to treating patients with some types of prostate cancer, according to a new study presented November 7, 2001, at the American Society for Therapeutic Radiology and Oncology's Annual Meeting in San Francisco.

Between 1989 and 1992, more than 200 patients with prostate specific antigen (PSA) levels greater than 10 ng/ml (0 to 4.0 are considered normal levels) participated in a dose escalation study. In it, patients received increasing doses of radiation therapy ranging from 68 Gy to 79 Gy. This earlier study has allowed the researchers in this article to conduct one of the first studies to examine long-term response to the treatment involving patients who completed treatment 8 to 12 years ago.

"Long-term evaluation of the advantage of radiation dose escalation in prostate cancer is important," said Gerald E. Hanks, retired chairman of the Radiation Oncology Department at Fox Chase Cancer Center in Philadelphia and lead author of the study. "This affords an opportunity to better understand dose response, side effects and the long-term effects of dose escalation, such as reducing metastasis rates."

For the study, 232 consecutive patients received increasing radiation doses. Follow-up was available in all but three patients. Sixty-nine patients are living cancer free, 54 living patients have reported PSA failure and 8 patients have reported metastasis. Seventeen patients died of cancer and 81 died of other causes.

With this long-term follow-up, disease relapse as measured by post-treatment PSA level was estimated for various patient groups according to the dose received.

"This long-term report of one of the earliest dose escalation series shows dose is critical for the unfavorable low PSA group and the intermediate PSA group," said Hanks. "Also treatment success is improved by approximately 40 percent, and distant metastases are reduced significantly for those patients with an initial PSA of 10 to 19.9.

"With enough patients and time, the latter observation must translate into better survival. The raising of the radiation dose remains one of the most important goals for the standard of treatment," Hanks added.

If you would like a copy of the abstract titled "Dose Response in Prostate Cancer with 8-12 Years Follow Up" or to speak to the lead author of the study, Gerald Hanks, M.D., please call Katherine Egan Bennett at the ASTRO Press Room at the Moscone Convention Center at (415) 978-3717 or e-mail her at [email protected]. Alternatively, you can call Lesley Nevers at ASTRO's headquarters at (703) 227-0141 or e-mail her at [email protected] for more information.

ASTRO is the largest radiation oncology society in the world, with more than 6,700 members who specialize in treating patients with radiation therapies. As a leading organization in radiation oncology, biology and physics, the society's goals are to advance the scientific base of radiation therapy and to extend the benefits of radiation therapy to those with cancer and other diseases.

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